power storage module

Abstract

Provided is a power storage module capable of suppressing short-circuiting of power storage units adjacent to each other when liquid reaches between the power storage units, the power storage module including: first and second power storage units each including a case having an upper surface and an external terminal provided to the upper surface, the first and second power storage units being arranged adjacent to each other; and a spacer arranged between the cases adjacent to each other and having insulating properties. An outlet portion for discharging liquid that has reached the spacer from above to the outside of the spacer is provided to the spacer.

Description

Technical Field

[0001] This disclosure relates to an energy storage module mounted in a vehicle. Background Technology

[0002] As an existing energy storage module, Japanese Patent Application Publication No. 2013-041708 discloses the following technology: a protrusion protruding to the side is provided at the upper end of the side of a spacer disposed between adjacent energy storage cells, and an inclined surface is provided on the upper surface of the protrusion, which slopes downwards as it moves away from the side of the spacer. Therefore, foreign objects falling onto the protrusion will fall along the inclined surface, thus preventing the accumulation of foreign objects in the protrusion. Summary of the Invention

[0003] Regarding the energy storage module disclosed in Japanese Patent Application Publication No. 2013-041708, although the inclined surface of the protrusion can suppress the accumulation of foreign matter such as dust on the protrusion, the upper surface of the spacer is flat. Therefore, when liquids such as dew reach the upper surface of the spacer, the liquid cannot move and will remain on the upper surface of the spacer. In this case, it may cause a short circuit between adjacent energy storage cells.

[0004] This disclosure is made in view of the aforementioned problems, and the object of this disclosure is to provide an energy storage module that can suppress short circuits between adjacent energy storage units when liquid reaches between them.

[0005] The energy storage module disclosed herein includes: a first energy storage unit and a second energy storage unit, each comprising a frame having an upper surface and an external terminal disposed on the upper surface, the first energy storage unit and the second energy storage unit being arranged adjacent to each other; and a spacer disposed between the adjacent frames and having insulating properties. A discharge portion is provided on the spacer for discharging liquid that has reached the spacer from the upper side to the outside of the spacer.

[0006] According to the above structure, by providing a discharge section in the spacer, liquid that has reached the spacer from the upper side can be discharged to the outside of the spacer. This prevents the surface distance between the external terminals of adjacent energy storage units from decreasing due to liquid retention. As a result, insulation between the external terminals of adjacent energy storage units can be ensured, preventing short circuits between adjacent energy storage units.

[0007] In the energy storage module based on the present disclosure, the spacer has an upper surface portion located at a position lower than the upper surface of the frame. The upper surface portion may also have an inclined surface that slopes downwards toward a direction orthogonal to both the arrangement direction and the vertical direction, wherein the arrangement direction is the direction in which the first energy storage unit and the second energy storage unit are arranged side-by-side. In this case, the discharge portion is formed by the inclined surface.

[0008] According to the above structure, by providing an inclined surface on the upper surface of the spacer, even if the liquid reaches the upper surface of the spacer, the liquid can be discharged out of the spacer using the inclined surface.

[0009] In the energy storage module based on the present disclosure, the spacer may also include one or more discharge paths communicating in the vertical direction. In this case, the discharge section is composed of one or more discharge paths, where the length of the frame in the direction orthogonal to the arrangement direction and the vertical direction is defined as A (mm), the distance between adjacent frames is defined as B (mm), and the total flow area of ​​the one or more discharge paths in the cross-section of the spacer orthogonal to the vertical direction is defined as C (mm²). 2 In the case of ), it is preferable that C / (A×B) is 1% or more and 50% or less, wherein the above arrangement direction is the arrangement direction in which the first energy storage unit and the second energy storage unit are arranged side by side.

[0010] According to the above structure, by setting C / (A×B) to 1% or more and 50% or less as described above, the liquid that has reached the spacer from the top side can be discharged to the outside of the spacer through the discharge path, and the spacer can be prevented from breaking when an impact is input to the spacer from the outside.

[0011] According to this disclosure, an energy storage module can be provided that can suppress short circuits between adjacent energy storage cells caused by the liquid when the liquid reaches between them. Attached Figure Description

[0012] The features, advantages, technical significance, and industrial significance of exemplary embodiments of the present invention will now be described with reference to the accompanying drawings, in which like reference numerals denote like elements, wherein:

[0013] Figure 1 This is a top view of the energy storage module in Implementation Method 1.

[0014] Figure 2 This is a diagram showing the spacer and the energy storage unit located behind the spacer of the energy storage module in Embodiment 1, viewed from the front.

[0015] Figure 3This is a diagram showing the spacer and the energy storage unit located behind the spacer of the comparative example's energy storage module, viewed from the front.

[0016] Figure 4 This is a diagram used to illustrate the surface distance between adjacent external terminals in the energy storage module of the comparative example.

[0017] Figure 5 This is a diagram showing the state in which liquid is stored on the upper surface of the spacer in the energy storage module of the comparative example.

[0018] Figure 6 This is a diagram showing the spacer and the energy storage unit located behind the spacer of the energy storage module in Embodiment 2, viewed from the front.

[0019] Figure 7 This is a diagram showing the spacer and the energy storage unit located behind the spacer of the energy storage module in Embodiment 3, viewed from the front.

[0020] Figure 8 This is a top view showing a portion of the energy storage module of Embodiment 3.

[0021] Figure 9 This is a diagram showing the spacer and the energy storage unit located behind the spacer of the energy storage module in Embodiment 4, viewed from the front.

[0022] Figure 10 This is a top view showing a portion of the energy storage module of Embodiment 4.

[0023] Figure 11 This is a diagram showing the spacer and the energy storage unit located behind the spacer of the energy storage module in Embodiment 5, viewed from the front.

[0024] Figure 12 This is a diagram showing the spacer and the energy storage unit located behind the spacer of the reference example energy storage module, viewed from the front. Detailed Implementation

[0025] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. It should be noted that in the embodiments shown below, the same or common parts are labeled with the same reference numerals in the drawings and their descriptions are not repeated.

[0026] (Implementation Method 1)

[0027] Figure 1 This is a top view of the energy storage module according to Embodiment 1. (Refer to...) Figure 1 The energy storage module 100 is used to illustrate the implementation method.

[0028] The energy storage module 100 of Embodiment 1 is mounted on a hybrid vehicle that can drive using the power of at least one of an electric motor and an engine, or an electric vehicle that can drive using driving force obtained from electrical energy.

[0029] The energy storage module 100 includes a plurality of energy storage units 21 and a plurality of spacers 30. The plurality of energy storage units 21 and the plurality of spacers 30 are arranged alternately along a predetermined arrangement direction.

[0030] The energy storage unit 21 is, for example, a secondary battery such as a nickel-metal hydride battery or a lithium-ion battery. A single cell may have a square shape, for example. The secondary battery can be a battery using a liquid electrolyte or a battery using a solid electrolyte. Alternatively, the energy storage unit may also be configured as a unit capacitor capable of storing electricity.

[0031] The energy storage unit 21 has a frame 22, a positive terminal 23 and a negative terminal 24 as external terminals. A battery element (not shown) is housed inside the frame 22. The positive terminal 23 and the negative terminal 24 are disposed on the upper surface 22a of the frame 22. The positive terminal 23 is electrically connected to the positive side of the battery element. The negative terminal 24 is electrically connected to the negative side of the battery element. It should be noted that the positive terminal 23 and the negative terminal 24 are insulated from the frame 22 by an insulating member (not shown).

[0032] The plurality of energy storage units 21 include a first energy storage unit 21a and a second energy storage unit 21b that are adjacent to each other in the above-mentioned arrangement direction. The first energy storage unit 21a and the second energy storage unit 21b are arranged in the above-mentioned arrangement direction with the positive terminal 23 and the negative terminal 24 alternately side by side.

[0033] Spacer 30 is disposed between adjacent energy storage units 21. Spacer 30 is disposed between the first energy storage unit 21a and the second energy storage unit 21b. More specifically, spacer 30 is disposed between the frame 22 of the first energy storage unit 21a and the frame 22 of the second energy storage unit 21b.

[0034] The spacer 30 is insulating. The spacer 30 is made of an insulating resin component. The resin component can be made of polypropylene (PP), polyethylene (PE), polyethylene terephthalate (PET), polystyrene (PS), or polycarbonate (PC), etc.

[0035] Figure 2 This is a diagram showing the spacer and the energy storage unit located behind the spacer of the energy storage module in Embodiment 1, viewed from the front.

[0036] like Figure 1 and Figure 2As shown, the spacer 30 has a plate-like shape. A discharge section 35 is provided on the spacer 30 for discharging liquid that has reached the spacer 30 from the upper side to the outside of the spacer.

[0037] The spacer 30 has an upper surface portion 30a and a bottom portion 30b. The upper surface portion 30a is located in the vertical direction ( Figure 2 The upper end of the spacer 30 in the DR1 direction is located on the upper surface 30a, which is lower than the upper surface 22a of the frame 22 of the energy storage unit 21. The contact angle between this upper surface 30a and water is, for example, about 80 degrees. The lower end of the spacer 30 in the vertical direction is located on the lower end of the spacer 30.

[0038] In embodiment 1, the upper surface portion 30a has a width direction that is orthogonal to the above-mentioned arrangement direction and vertical direction ( Figure 2 The inclined surface (in the DR2 direction) slopes downwards from one side to the other. This inclined surface constitutes the discharge section 35. Preferably, the inclination angle θ of the inclined surface intersecting the width direction is 1 degree or more. By setting the inclination angle θ to 1 degree or more, the liquid can move more reliably along the inclined surface.

[0039] Although the energy storage module 100 is housed within a housing (not shown), condensation may sometimes occur when it is cooled within the housing. Additionally, there is a possibility of liquid intrusion into the housing. In such cases, liquid may sometimes reach the spacer 30 from the upper side.

[0040] When liquid reaches the spacer 30 from the upper side, it can be discharged to the outside of the spacer 30 via the discharge section 35. Specifically, the liquid is discharged to the outside of the spacer 30 by flowing along the inclined surface of the upper surface portion 30a. As a result, the surface distance between the external terminals of adjacent energy storage cells 21 can be prevented from decreasing due to liquid retention. Consequently, the insulation between the external terminals of adjacent energy storage cells 21 can be ensured, and short circuits between adjacent energy storage cells 21 can be prevented.

[0041] It should be noted that, regarding the surface distance between the external terminals of adjacent energy storage units 21, the following is used: Figure 4 and Figure 5 The following will be described.

[0042] (Comparative Example)

[0043] Figure 3 This diagram shows a frontal view of the spacer and the energy storage unit located behind the spacer in the comparative example's energy storage module. (Refer to...) Figure 3 The energy storage module 100X is used to illustrate the comparative example.

[0044] like Figure 3 As shown, when comparing the energy storage module 100X of the comparative example with the energy storage module 100 of Embodiment 1, the shape of the spacer 30X is different. Other structures are largely the same. In the spacer 30X, the upper surface portion 30a is formed flat.

[0045] Figure 4 This is a diagram used to illustrate the surface distance between adjacent external terminals in the energy storage module of the comparative example.

[0046] When the length from the positive terminal 23 to the upper surface 22a of the frame 22 along the vertical direction is set as b (mm), the length from the upper surface 22a of the frame 22 to the upper surface portion 30a of the spacer 30X along the vertical direction is set as a (mm), the distance from the side of the frame 22 to the side of the positive terminal 23 along the arrangement direction is set as c (mm), and the distance from the center portion of the spacer 30X to the side of the frame 22 along the arrangement direction is set as d (mm), the insulation between the external terminals of adjacent energy storage units 21 depends on the surface distance (a+b+c+d) at the closest point between the external terminals.

[0047] Figure 5 This is a diagram showing the state in which liquid is stored on the upper surface of the spacer in the energy storage module of the comparative example.

[0048] like Figure 5 As shown, in the comparative example, the upper surface portion 30a of the spacer 30X is flat, so the liquid L reaching the spacer 30X from the upper side will remain on the upper surface portion 30a. In this case, when the length along the vertical direction from the liquid surface to the upper surface 22a of the frame 22 is set as a1 (mm), the above-mentioned surface distance becomes a1+b+c+d.

[0049] a1 (mm) is smaller than a (mm) mentioned above, and the distance along the surface (a1+b+c+d) when the liquid remains on the upper surface portion 30a is smaller than... Figure 4 The liquid, as shown, does not have a smaller surface distance when it remains on the upper surface portion 30a. As a result, in the comparative example energy storage module 100X, the insulation between adjacent external terminals is reduced due to the liquid L remaining on the upper surface portion 30a of the spacer 30X, which may cause a short circuit in adjacent energy storage cells 21.

[0050] (Implementation Method 2)

[0051] Figure 6 This is a frontal view of the energy storage module of Embodiment 2, showing the spacer and the energy storage unit located behind the spacer. (Refer to...) Figure 6 The energy storage module 100A of embodiment 2 will be described below.

[0052] like Figure 6 As shown, when comparing the energy storage module 100A of Embodiment 2 with the energy storage module 100 of Embodiment 1, the shape of the spacer 30A is different. The other structures are roughly the same.

[0053] like Figure 6 As shown, the upper surface portion 30a of the spacer 30A has a first inclined surface 30a1 and a second inclined surface 30a2. In Embodiment 2, the discharge portion 35 is formed by the first inclined surface 30a1 and the second inclined surface 30a2.

[0054] The first inclined surface 30a1 is inclined downwards as it moves from the center of the spacer 30A in the width direction toward one side in the width direction. Preferably, the inclination angle θ1 of the first inclined surface 30a1 intersecting the width direction is 1 degree or more.

[0055] The second inclined surface 30a2 is inclined downwards as it moves from the center of the spacer 30A in the width direction toward the other side in the width direction. Preferably, the inclination angle θ2 of the second inclined surface 30a2 intersecting the width direction is 1 degree or more.

[0056] By setting the aforementioned tilt angles θ1 and θ2 to 1 degree or more, the liquid can move more reliably along the tilted surface.

[0057] With this configuration, the energy storage module 100A of Embodiment 2 also has approximately the same effect as the energy storage module 100 of Embodiment 1.

[0058] (Implementation Method 3)

[0059] Figure 7 This is a diagram showing the spacer and the energy storage unit located behind the spacer of the energy storage module in Embodiment 3, viewed from the front. Figure 8 This is a top view showing a portion of the energy storage module of Embodiment 3. (Refer to...) Figure 7 and Figure 8 The energy storage module 100B of embodiment 3 will be described below.

[0060] like Figure 7 and Figure 8 As shown, when comparing the energy storage module 100B of Embodiment 3 with the energy storage module 100 of Embodiment 1, the shape of the spacer 30B is different. The other structures are roughly the same.

[0061] The spacer 30B includes a flat plate portion 31 and a plurality of protrusions 32. The flat plate portion 31 is substantially parallel to the vertical direction and the aforementioned width direction. The upper surface of the flat plate portion 31 is substantially parallel to the width direction. The flat plate portion 31 abuts against the frame 22 of one of the adjacent energy storage units 21 (first energy storage unit 21a). The flat plate portion 31 has a substantially rectangular shape when viewed from the front (when viewed from the arrangement direction).

[0062] Multiple protrusions 32 protrude from the flat plate portion 31 toward the other energy storage unit (second energy storage unit 21b) in the adjacent energy storage units 21. The multiple protrusions 32 are arranged extending vertically and spaced apart in the width direction. Each protrusion 32 has a columnar shape, with an upper surface and a bottom surface at both ends in the vertical direction. Specifically, the multiple protrusions 32 have a quadrangular prism shape. The ends of the multiple protrusions 32 in the aforementioned arrangement direction abut against the frame 22 of the second energy storage unit 21b.

[0063] By forming multiple protrusions 32 in this way, multiple discharge passages 33 communicating in the vertical direction are formed in the spacer 30B. In this embodiment, the discharge section 35 is constituted by one or more discharge passages 33.

[0064] In this case, when the length of the frame 22 in the width direction is set to A (mm), the distance between adjacent frames 22 in the arrangement direction is set to B (mm), and the total flow area of ​​the multiple discharge flow paths 33 at the cross-section of the spacer 30B orthogonal to the vertical direction is set to C (mm) 2 Preferably, C / (A×B) is 1% or more and 50% or less.

[0065] When liquid reaches spacer 30B from the upper side, the liquid can be discharged downwards through multiple discharge paths 33. Furthermore, by setting C / (A×B) to 1% or more and 50% or less, damage to the spacer 30B can be suppressed when an impact is input from the outside.

[0066] In the energy storage module 100B configured in this way, the effects are substantially the same as those of the energy storage module 100 in Embodiment 1.

[0067] It should be noted that in the above-described embodiment 3, the case in which multiple discharge flow paths 33 are provided in the spacer 30B is illustrated, but it is not limited to this. As long as the discharge flow path 33 can discharge liquid, one or more can be provided.

[0068] (Implementation Method 4)

[0069] Figure 9This is a diagram showing the spacer and the energy storage unit located behind the spacer of the energy storage module in Embodiment 4, viewed from the front. Figure 10 This is a top view showing a portion of the energy storage module of Embodiment 4. (Refer to...) Figure 9 and Figure 10 The energy storage module 100C of embodiment 4 will be described below.

[0070] like Figure 9 and Figure 10 As shown, when the energy storage module 100C of Embodiment 4 is compared with the energy storage module 100B of Embodiment 3, the shape of the spacer 30C is different. The other structures are roughly the same.

[0071] When spacer 30C is compared with spacer 30B of embodiment 2, the shapes of the plurality of protrusions 32C are different. The plurality of protrusions 32C have a columnar shape, which has an upper surface portion and a bottom surface portion at both ends in the arrangement direction. Specifically, the plurality of protrusions 32C have a cylindrical shape.

[0072] Multiple protrusions 32C are spaced apart from each other in a serrated arrangement. By forming multiple protrusions 32C in this way, multiple discharge passages communicating in the vertical direction are formed in the spacer 30C. The discharge section 35 is constituted by these multiple discharge passages.

[0073] In this embodiment, the length of the frame 22 in the width direction is set as A (mm), the distance between adjacent frames 22 in the arrangement direction is set as B (mm), and the total flow area of ​​the plurality of discharge flow paths 33 at the cross-section of the spacer 30C orthogonal to the vertical direction is set as C (mm²). 2 When C / (A×B) is used, it is preferred that C / (A×B) be 1% or more and 50% or less.

[0074] With this configuration, the energy storage module 100C of Embodiment 4 can also achieve approximately the same effect as the energy storage module 100B of Embodiment 3.

[0075] (Implementation Method 5)

[0076] Figure 11 This is a frontal view of the energy storage module of Embodiment 5, including the spacer and the energy storage unit located behind the spacer. (Refer to...) Figure 11 The energy storage module 100D of embodiment 5 will be described below.

[0077] like Figure 11 As shown, when the energy storage module 100D of Embodiment 5 is compared with the energy storage module 100 of Embodiment 1, the shape of the upper surface portion 30a of the spacer 30D is different. The other structures are roughly the same.

[0078] The upper surface portion 30a of the spacer 30D has a curved surface that bulges upward from the center portion in the width direction compared to both ends in the width direction. In this case, the discharge portion 35 is formed by the curved surface.

[0079] When the upper surface portion 30a is thus designed as a curved surface, the liquid can be discharged to the outside of the spacer 30D by allowing the liquid to flow along the curved surface. It should be noted that the radius of curvature of the curved surface is preferably, for example, R1000 or less. By setting such a radius of curvature, the liquid can move along the curved surface, and the liquid can be discharged to the outside of the spacer 30D more reliably.

[0080] With the configuration described above, the energy storage module 100D of Embodiment 5 can also achieve approximately the same effect as the energy storage module 100 of Embodiment 1.

[0081] (Example for reference)

[0082] Figure 12 This diagram shows a frontal view of the energy storage module in the reference example, including the spacer and the energy storage unit located behind the spacer. (Refer to...) Figure 12 The reference example is the energy storage module 100E.

[0083] like Figure 12 As shown, when comparing the energy storage module 100E of the reference example with the energy storage module 100X of the comparative example, the difference lies in the application of a hydrophobic treatment to the upper surface portion 30a of the spacer 30E. This hydrophobic treatment results in a contact angle of approximately 150 degrees or more between the upper surface portion 30a and water.

[0084] In this case, by means of hydrophobic treatment, the liquid that reaches the spacer 30E from the upper side can also be discharged to the outside of the spacer 30.

[0085] The embodiments disclosed herein are illustrative and not restrictive in all respects. The scope of the invention is defined by the claims, which include all modifications within the meaning and scope of the claims.

Claims

1. An energy storage module, wherein, have: A first energy storage unit and a second energy storage unit, each comprising a frame having an upper surface and an external terminal disposed on the upper surface, wherein the first energy storage unit and the second energy storage unit are arranged adjacent to each other. as well as Spacers, which are disposed between adjacent frames and are insulating, The spacer has an upper surface portion located at a position lower than the upper surface of the frame. The entire upper surface is an inclined surface, which slopes downwards toward a side of the width direction that is orthogonal to the arrangement direction of the first and second energy storage units and the vertical direction. The spacer is provided with a discharge portion for discharging liquid that has reached the spacer from the upper side to the outer side of the spacer in the width direction. The discharge section is formed by the inclined surface. The upper surface portion has a lower end located on one side in the width direction and an upper end located on the other side in the width direction. The inclined surface connects the lower end and the upper end.

2. An energy storage module, wherein, have: A first energy storage unit and a second energy storage unit, each comprising a frame having an upper surface and an external terminal disposed on the upper surface, wherein the first energy storage unit and the second energy storage unit are arranged adjacent to each other. as well as Spacers, which are disposed between adjacent frames and are insulating, The spacer has an upper surface portion located at a position lower than the upper surface of the frame. A portion of the upper surface is a first inclined surface, and the remaining portion is a second inclined surface. The entire first inclined surface is inclined downwards as it moves from the center of the spacer in the width direction toward one side of the width direction. The entire second inclined surface is inclined downwards as it moves from the center of the spacer in the width direction toward the other side of the width direction. The width direction is orthogonal to the arrangement direction of the first and second energy storage units and the vertical direction. The spacer is provided with a discharge portion for discharging liquid that has reached the spacer from the upper side to the outer side of the spacer in the width direction. The discharge section is composed of the first inclined surface and the second inclined surface.

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